Capacitors having separate terminals on three or more sides

ABSTRACT

A multilayer capacitor comprises separate terminals on at least three sides, and on as many as six sides. The capacitor can be fabricated in a large number of different configurations, types, and sizes, depending upon the target application. The separate terminals that are disposed on different sides of the capacitor can be readily coupled to a variety of different adjacent conductors, such as die terminals (including bumpless terminals or bars), IC package terminals (including pads or bars), and the terminals of adjacent discrete components. Methods of fabrication, as well as application of the capacitor to an electronic assembly, are also described.

RELATED APPLICATIONS

The present application is related to the following applications whichare assigned to the same assignee as the present application:

Ser. No. 10/006,292, entitled “Integrated Circuit Packages WithSandwiched Capacitors”, now U.S. Pat. No. 6,900,991; and

Ser. No. 11/080,126, entitled “Integrated Circuit Packages WithSandwiched Capacitors”.

TECHNICAL FIELD

The inventive subject matter relates generally to electronic components.More particularly, the inventive subject matter relates to amulti-terminal capacitor, to an electronic assembly that includes amulti-terminal capacitor, and to fabrication methods related thereto.

BACKGROUND INFORMATION

Integrated circuits (ICs) are typically assembled into packages byphysically and electrically coupling them to a substrate made of organicor ceramic material. One or more ICs or IC packages can be physicallyand electrically coupled to a substrate such as a printed circuit board(PCB) or card to form an “electronic assembly”. The “electronicassembly” can be part of an “electronic system”. An “electronic system”is broadly defined herein as any product comprising an “electronicassembly”.

Examples of electronic systems include computers (e.g., desktops,laptops, hand-helds, servers, Web appliances, routers, etc.), wirelesscommunications devices (e.g., cellular phones, cordless phones, pagers,personal digital assistants, etc.), computer-related peripherals (e.g.,printers, scanners, monitors, etc.), entertainment devices (e.g.,televisions, radios, stereos, tape and compact disc players, videocassette recorders, camcorders, digital cameras, MP3 (Motion PictureExperts Group, Audio Layer 3) players, video games, watches, etc.), andthe like.

In the field of electronic systems there is an incessant competitivepressure among manufacturers to increase the performance of theirequipment. This is particularly true regarding the packaging of ICs onsubstrates, where each new generation of packaging must provideincreased performance, particularly in terms of an increased number ofcomponents and higher clock frequencies, while generally being smalleror more compact in size.

An IC substrate may comprise a number of insulated metal layersselectively patterned to provide metal interconnect lines (referred toherein as “traces”), and one or more electronic components mounted onone or more surfaces of the substrate. The electronic component orcomponents are functionally connected to other elements of an electronicsystem through a hierarchy of electrically conductive paths that includethe substrate traces. The substrate traces typically carry signals thatare transmitted between the electronic components, such as ICs, of thesystem.

As the internal circuitry of high performance ICs, such as processors,operates at higher and higher clock frequencies, noise in the power andground lines increasingly reaches an unacceptable level. This noise canarise due to inductive and capacitive parasitics, for example, as iswell known. To reduce such noise, capacitors known as decoupling orby-pass capacitors are often used to provide a stable signal or stablesupply of power to the circuitry.

As electronic devices continue to advance, there is an increasing needfor higher levels of capacitance at reduced inductance levels fordecoupling, power dampening, and supplying charge. In addition, there isa need for capacitance solutions that do not interfere with packageconnectors of various types, and which do not limit the industry tocertain device sizes and packing densities. Accordingly, there is a needin the art for alternative capacitance solutions in the fabrication andoperation of electronic devices and their packages.

Many types of capacitors are known in the electronic arts. One knowntype of capacitor used in electronic assemblies is referred to a “chipcapacitor”. Chip capacitors are known, for example, in dual-terminalconfigurations. FIG. 1 is a prior art dual-terminal chip capacitor 1.These are currently available in a number of different sizes, such as“0402”, i.e. 0.040″×0.020″ (approx. 1.0 mm×0.50 mm). 0402 capacitorstypically have a wrap-around terminal on each end, i.e. a terminal 2 or3 covers each end and a portion of each side. One terminal 2 is of afirst polarity, and the other terminal 3 is of a second polarity.

In addition to dual-terminal chip capacitors, another type of chipcapacitor is referred to as an “interdigitated capacitor”. FIG. 2 is aprior art interdigitated capacitor 4 having several terminals 5–8 oneach of two sides. Terminals 5 and 7 are of a first polarity type, andterminals 6 and 8 are of a second polarity type. Terminals of the samepolarity type are alternated along two opposing sides of capacitor 4.Interdigitated, multilayer, ceramic capacitors are commerciallyavailable from AVX, Myrtle Beach, S.C., whose URL is currentlywww-avxcorp-com; TDK Corporation, Mount Prospect, Ill., whose URL iscurrently www-tdk-com; and Murata Electronics, Smyrna, Ga., whose URL iscurrently www-murata-com. (To avoid inadvertent hyperlinks, the periodsin the preceding URLs have been replaced by hyphens.)

Dual-terminal chip capacitors and interdigitated caps, while adequatefor many packaging and other electronic applications, are not versatileenough to accommodate the design and performance requirements of manycurrent electronic applications, including the packaging of highperformance ICs.

For the reasons stated above, and for other reasons stated below whichwill become apparent to those skilled in the art upon reading andunderstanding the present specification, there is a significant need inthe art for improved multi-terminal capacitors, for improved electronicassemblies incorporating such multi-terminal capacitors, and forimproved methods of fabricating such multi-terminal capacitors andelectronic assemblies.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a prior art dual-terminal chip capacitor;

FIG. 2 is a prior art interdigitated capacitor having several terminalson each of two sides;

FIG. 3 is a top view of a multi-terminal capacitor having separateterminals on three sides, in accordance with an embodiment of theinventive subject matter;

FIG. 4 is a bottom view of the multi-terminal capacitor shown in FIG. 3;

FIG. 5 is an exploded perspective view of the multi-terminal capacitorshown in FIG. 3;

FIG. 6 is a top view of a multi-terminal capacitor having separateterminals on four sides, in accordance with an embodiment of theinventive subject matter;

FIG. 7 is a bottom view of the multi-terminal capacitor shown in FIG. 6;

FIG. 8 is an exploded perspective view of the multi-terminal capacitorshown in FIG. 6;

FIG. 9 is a top view of a multi-terminal capacitor having separateterminals on six sides, in accordance with an embodiment of theinventive subject matter;

FIG. 10 is a bottom view of the multi-terminal capacitor shown in FIG.9;

FIG. 11 is an exploded perspective view of the multi-terminal capacitorshown in FIG. 9;

FIG. 12 is a top view of a multi-terminal capacitor having separateterminals on at least three sides, in accordance with an embodiment ofthe inventive subject matter;

FIG. 13 illustrates a cross-sectional representation of an electronicassembly, including an electrical element, a multi-terminal capacitorhaving separate terminals on at least three sides, and a substrate, inaccordance with an embodiment of the inventive subject matter;

FIGS. 14A and 14B together illustrate a flow diagram of a method offabricating a multi-terminal capacitor having separate terminals onthree or more sides, in accordance with an embodiment of the inventivesubject matter;

FIGS. 15A and 15B together illustrate a flow diagram of a method offabricating an electronic assembly comprising a substrate and amulti-terminal capacitor having separate terminals on three or moresides, in accordance with an embodiment of the inventive subject matter;and

FIGS. 16A, 16B, and 16C together illustrate a flow diagram of a methodof fabricating an electronic assembly comprising a substrate, anelectrical element, and a multi-terminal capacitor having separateterminals on three or more sides, in accordance with an embodiment ofthe inventive subject matter.

DETAILED DESCRIPTION

In the following detailed description of embodiments of the inventivesubject matter, reference is made to the accompanying drawings whichform a part hereof, and in which is shown by way of illustrationspecific preferred embodiments in which the inventive subject matter maybe practiced. These embodiments are described in sufficient detail toenable those skilled in the art to practice them, and it is to beunderstood that other embodiments may be utilized and that structural,mechanical, compositional, and electrical changes may be made withoutdeparting from the spirit and scope of the inventive subject matter. Thefollowing detailed description is, therefore, not to be taken in alimiting sense, and the scope of the inventive subject matter is definedonly by the appended claims.

The inventive subject matter provides a multilayer capacitor that hasseparate terminals on at least three sides, and on as many as six sides.The capacitors can be fabricated in a large number of differentconfigurations, types, and sizes, depending upon the target application.

The term “separate”, as used herein, means that a terminal is notelectrically coupled to another terminal via any element that is on theexterior of the capacitor. For example, a terminal that is wrappedaround an edge of the capacitor does not thereby form two “separate”terminals. As another example, terminals that are only electricallycoupled via an element that is on the interior of the capacitor are“separate” terminals. The term “separate” can apply to terminals thatare on the same side, or on different sides, of the capacitor.

For an application, used in a high performance electronic assembly asdescribed in the Related Applications, the capacitors are positionedwithin the mounting region between a die and an IC package substrate,particularly in a core region containing power conductors. Through thisarrangement, capacitors can be placed close to the IC to minimize loopinductance for power delivery, while also minimizing resistance losses.In addition, the use of ceramic capacitors between the IC and the ICpackage substrate in certain embodiments can provide an improved CTE(coefficient of thermal expansion) match and improved operationalreliability.

The capacitor has terminals on at least three sides, and up to sixsides. These terminals can be coupled to corresponding adjacentconductors, such as die terminals (including bumpless terminals), ICpackage terminals (including pads and/or bars), and the terminals ofadjacent discrete components (including additional capacitors). Variousembodiments of capacitors having separate terminals on three or moresides are illustrated and described herein. Methods of fabrication, aswell as application of the capacitors to an electronic assembly, arealso described.

FIG. 3 is a top view of a multi-terminal capacitor 10 having separateterminals on three sides, in accordance with an embodiment of theinventive subject matter. Capacitor 10 has two terminals 12 of positivepolarity and two terminals 14 of negative polarity on its upper surface.Terminals 12 and 14 are “separate” terminals as defined above.

Capacitor 10 has a terminal 16 of negative polarity on its left-hand end(refer to FIG. 5), which terminal 16 has an upper portion 15 that wrapsaround onto the top of capacitor 10. Capacitor 10 further has a terminal19 of positive polarity on its right-hand end (refer to FIG. 5), whichterminal 19 has an upper portion 18 that wraps around onto the top ofcapacitor 10. In another embodiment, terminals 16 and 19 do not haveportions that wrap onto the top of capacitor 10. Terminals 16 and 19(FIG. 5) are “separate” terminals.

FIG. 4 is a bottom view of the multi-terminal capacitor 10 shown in FIG.3. In the embodiment illustrated, terminal 16 (refer to FIG. 5) has alower portion 17 (FIG. 4) that wraps around onto the bottom of capacitor10. Terminal 19 (refer to FIG. 5) has a lower portion 20 (FIG. 4) thatwraps around onto the bottom of capacitor 10. In another embodiment,terminals 16 and 19 do not have portions that wrap onto bottom ofcapacitor 10.

FIG. 5 is an exploded perspective view of the multi-terminal capacitor10 shown in FIG. 3. Capacitor 10 comprises upper and lower layers 31 and32, respectively, which may be insulators. Upper layer 31 is oftenreferred to in the art as a “capping layer”, and lower layer 32 is oftenreferred to as a “base layer”.

Upper layer 31 comprises terminals 12 and 14. Lower layer 32 does notcomprise any separate terminals in this embodiment. However, portion 17of terminal 16 wraps around onto lower layer 32, and portion 20 ofterminal 19 wraps around onto lower layer 32.

Capacitor 10 also includes four conductive plates 21-24. Conductiveplates 21 and 22 are charge-storing elements to hold an electricalcharge of a first polarity, e.g. a positive charge. Conductive plates 23and 24 are charge-storing elements to hold an electrical charge of asecond polarity, e.g. a negative charge. Conductive plates 21–24 can befabricated of any suitable material. For example, they could be formedof a metal such as copper, aluminum, or of a metal alloy. Conductiveplates 21–24 may be separated by a suitable dielectric material, such asplastic, a ceramic, a polymer, glass, or air.

“Suitable”, as used herein, means having characteristics that aresufficient to produce the desired result(s). Suitability for theintended purpose can be determined by one of ordinary skill in the artusing only routine experimentation.

Conductive plates 21–24 are generally disposed within the interior ofthe body of capacitor 10. In the embodiment shown in FIG. 5, conductiveplates 21 and 22 are offset slightly to the right, so that they makeelectrical contact with terminal 19 when capacitor 10 is assembled.Similarly, conductive plates 23 and 24 are offset slightly to the left,so that they make electrical contact with terminal 16 when capacitor 10is assembled.

Terminals 12 on the upper surface of capacitor 10 are electricallycoupled to conductive plates 21 and 22 by means of a conductor such asvia 41. Via 41 passes through a non-contact or keep-out area 42 ofconductive plate 23 without electrically contacting conductive plate 23.Similarly, terminals 14 on the upper surface of capacitor 10 areelectrically coupled to conductive plates 23 and 24 by means of aconductor such as via 43, which passes through keep-out areas 44 and 45of conductive plates 21 and 22, respectively. Vias 41 and 43 can be ofany suitable type, geometry, and composition.

Referring to FIG. 5, although one terminal of each polarity isillustrated on the ends of capacitor 10, and two terminals of eachpolarity are illustrated on the top of capacitor 10, capacitor 10 couldhave more separate terminals of the same and/or opposite polarity on itsends, and capacitor 10 could have fewer separate terminals on its top.For example, capacitor 10 could have only one terminal 12 and only oneterminal 14 on its top.

FIG. 6 is a top view of a multi-terminal capacitor 100 having separateterminals on four sides, in accordance with an embodiment of theinventive subject matter. Capacitor 100 has two terminals 112 ofpositive polarity and two terminals 114 of negative polarity on its top.Terminals 112 and 114 are “separate” terminals as defined above.

Capacitor 100 has a terminal 116 of negative polarity on its left-handend (refer to FIG. 8), which terminal 116 has an upper portion 115 thatwraps around onto the top of capacitor 100. Capacitor 100 further has aterminal 119 of positive polarity on its right-hand end (refer to FIG.8), which terminal 119 has an upper portion 118 that wraps around ontothe top of capacitor 100. In another embodiment, terminals 116 and 119do not have portions that wrap onto the top of capacitor 100. Terminals116 and 119 (FIG. 8) are “separate” terminals.

FIG. 7 is a bottom view of the multi-terminal capacitor 100 shown inFIG. 6. Capacitor 100 has two terminals 111 of negative polarity and twoterminals 113 of positive polarity on its lower surface. Terminals 111and 113 are “separate” terminals as defined above.

In the embodiment illustrated, terminal 116 (refer to FIG. 8) has alower portion 117 (FIG. 7) that wraps around onto the bottom ofcapacitor 100. Terminal 119 (refer to FIG. 8) has a lower portion 120(FIG. 7) that wraps around onto the bottom of capacitor 100. In anotherembodiment, terminals 116 and 119 do not have portions that wrap ontobottom of capacitor 100.

FIG. 8 is an exploded perspective view of the multi-terminal capacitor100 shown in FIG. 6. Capacitor 100 comprises upper and lower layers 131and 132, respectively, which may be insulators. Upper layer 131comprises terminals 112 and 114. Lower layer 132 does not comprise anyseparate terminals in this embodiment. However, portion 117 of terminal116 wraps around onto lower layer 132, and portion 120 of terminal 119wraps around onto lower layer 132.

Capacitor 100 also includes four conductive plates 121–124. Conductiveplates 121 and 122 are charge-storing elements to hold an electricalcharge of a first polarity, e.g. a positive charge. Conductive plates123 and 124 are charge-storing elements to hold an electrical charge ofa second polarity, e.g. a negative charge. Conductive plates 121–124 canbe fabricated of any suitable material, such as a metal like copper,aluminum, nickel, silver, gold, tin, or a metal alloy, such as tin-lead,silver-lead, or silver-paladium. Conductive plates 121–124 may beseparated by a suitable dielectric material, such as any of thosementioned earlier.

Conductive plates 121–124 are generally disposed within the interior ofthe body of capacitor 100. In the embodiment shown in FIG. 8, conductiveplates 121 and 122 are offset slightly to the right, so that they makeelectrical contact with terminal 119 when capacitor 10 is assembled.Similarly, conductive plates 123 and 124 are offset slightly to theleft, so that they make electrical contact with terminal 116 whencapacitor 100 is assembled.

Terminals 112 on the upper surface of capacitor 100 are electricallycoupled to conductive plates 121 and 122, and to terminals 113 on thelower surface of capacitor 100, by means of a conductor such as via 141.Via 141 passes through non-contact or keep-out areas 142 and 146 ofconductive plates 121 and 123, respectively, without electricallycontacting conductive plates 121 or 123. Similarly, terminals 114 on theupper surface of capacitor 100 are electrically coupled to conductiveplates 123 and 124, and to terminals 111 on the lower surface ofcapacitor 100, by means of a conductor such as via 143, which passesthrough keep-out areas 144 and 145 of conductive plates 121 and 122,respectively.

Referring to FIG. 8, although one terminal of each polarity isillustrated on the ends of capacitor 100, and two terminals of eachpolarity are illustrated on the top and bottom of capacitor 100,capacitor 100 could have more separate terminals of the same and/oropposite polarity on its ends, and capacitor 100 could have fewerseparate terminals on its top and/or bottom. For example, capacitor 100could have only single terminals 112 and terminal 114 on its top, andonly single terminals 111 and 113 on its bottom.

FIG. 9 is a top view of a multi-terminal capacitor 200 having separateterminals on six sides, in accordance with an embodiment of theinventive subject matter. Capacitor 200 has two terminals 212 ofpositive polarity and two terminals 214 of negative polarity on its top.Terminals 212 and 214 are “separate” terminals as defined above.

Capacitor 200 has a terminal 216 of negative polarity on its left-handend (refer to FIG. 11), which terminal 216 has an upper portion 215 thatwraps around onto the top of capacitor 200. Capacitor 200 further has aterminal 219 of positive polarity on its right-hand end (refer to FIG.11), which terminal 219 has an upper portion 218 that wraps around ontothe top of capacitor 200.

In addition, capacitor 200 has a terminal 252 of positive polarity onits back side (refer to FIG. 11), which terminal 252 has an upperportion 251 that wraps around onto the top of capacitor 200. Capacitor200 further has a terminal 254 (only a portion of which is illustrated)of negative polarity on its front side (refer to FIG. 11), whichterminal 254 can have an upper portion (not shown) that wraps aroundonto the top of capacitor 200.

In another embodiment, terminals 216 and 219 do not have portions thatwrap onto the top of capacitor 200. Terminals 216, 219, 252, and 254(FIG. 11) are “separate” terminals. Thus capacitor 200 has separateterminals on six different sides. If a capacitor having separateterminals on five sides is desired, then separate terminals can beomitted from one of the sides.

FIG. 10 is a bottom view of the multi-terminal capacitor 200 shown inFIG. 9. Capacitor 200 has two terminals 211 of negative polarity and twoterminals 213 of positive polarity on its lower surface. Terminals 211and 213 are “separate” terminals as defined above.

In the embodiment illustrated, terminals 216 and 219 (refer to FIG. 11)have lower portions 217 and 220, respectively, that wrap around onto thebottom of capacitor 200. Also, terminals 251 and 254 (refer to FIG. 11)have lower portions 253 and 255, respectively, that wrap around onto thebottom of capacitor 200. In another embodiment, terminals 216, 219, 251,and 254 do not have portions that wrap onto bottom of capacitor 200.

FIG. 11 is an exploded perspective view of the multi-terminal capacitor200 shown in FIG. 9. Capacitor 200 comprises upper and lower layers 231and 232, respectively, which may be insulators. Upper layer 231comprises terminals 212 and 214. Lower layer 232 comprises terminals 211and 213.

Capacitor 200 also includes four conductive plates 221–224. Conductiveplates 221 and 222 are charge-storing elements to hold an electricalcharge of a first polarity, e.g. a positive charge. Conductive plates223 and 224 are charge-storing elements to hold an electrical charge ofa second polarity, e.g. a negative charge. Conductive plates 221–224 canbe fabricated of any suitable material, such as a metal like copper,aluminum, or a metal alloy. Conductive plates 221–224 may be separatedby a suitable dielectric material, such as any of those mentionedearlier.

Conductive plates 221–224 are generally disposed within the interior ofthe body of capacitor 200. In the embodiment shown in FIG. 11,conductive plates 221 and 222 are offset slightly to the right, so thatthey make electrical contact with terminal 219 when capacitor 200 isassembled. Similarly, conductive plates 223 and 224 are offset slightlyto the left, so that they make electrical contact with terminal 216 whencapacitor 200 is assembled. In addition, conductive plates 221 and 222can be offset slightly towards the rear, so that they make electricalcontact with terminal 252 when capacitor 200 is assembled. Likewise,conductive plates 223 and 224 can be offset slightly towards the front,so that they make electrical contact with terminal 254 when capacitor200 is assembled.

Terminals 212 on the upper surface of capacitor 200 are electricallycoupled to conductive plates 221 and 222, and to terminals 213 on thelower surface of capacitor 200, by means of a conductor such as via 241.Via 241 passes through non-contact or keep-out areas 242 and 246 ofconductive plates 221 and 223, respectively, without electricallycontacting conductive plates 221 or 223. Similarly, terminals 214 on theupper surface of capacitor 200 are electrically coupled to conductiveplates 223 and 224, and to terminals 211 on the lower surface ofcapacitor 200, by means of a conductor such as via 243, which passesthrough keep-out areas 244 and 245 of conductive plates 221 and 222,respectively.

Referring to FIG. 11, although one terminal of each polarity isillustrated on the front, back, and ends of capacitor 200, and twoterminals of each polarity are illustrated on the top and bottom ofcapacitor 200, capacitor 200 could have more separate terminals of thesame and/or opposite polarity on its front, back, and ends, andcapacitor 200 could have fewer separate terminals on its top and bottom.For example, capacitor 200 could have only single terminals 212 andterminal 214 on its top, and only single terminals 211 and 213 on itsbottom.

FIG. 12 is a top view of a multi-terminal capacitor 300 having separateterminals on at least three sides, in accordance with an embodiment ofthe inventive subject matter. On one surface, capacitor 300 has sixterminals that include three terminals 305 of positive polarity andthree terminals 307 of negative polarity. On a second surface, capacitor300 has a separate terminal 301 of positive polarity, and on a thirdsurface, capacitor 300 has a separate terminal 303 of negative polarity.Although the embodiment shown in FIG. 12 comprises terminals 301 and 303on opposite sides of capacitor 300, in other embodiments the separateterminals could be on any side. Also, although capacitor 300 comprisesterminals 301 and 303 having portions that wrap onto the same side asterminals 305 and 307, in another embodiments terminals 301 and 303 donot wrap onto the same side as other separate terminals. The internalstructure of capacitor 300 can be similar to that shown for capacitor100.

FIG. 13 illustrates a cross-sectional representation of an electronicassembly 400, including an electrical element 401, a multi-terminalcapacitor 410 having separate terminals on at least three sides, and asubstrate 430, in accordance with an embodiment of the inventive subjectmatter. Electronic assembly 400 illustrates merely one of many possibleembodiments in which capacitors having separate terminals on three ormore sides can be combined with a substrate, an electrical element, orboth.

In this embodiment, capacitor 410 comprises separate terminals on atleast four sides. Namely, capacitor 410 comprises a first terminal 421on its left-hand end, and capacitor 410 comprises a second terminal 422on its right-hand end. In addition, capacitor 410 comprises a pluralityof terminals 413 and 414 in or on its upper surface, and capacitor 410comprises a plurality of terminals 428 and 429 in or on its lowersurface. In this embodiment, the upper and lower surfaces of capacitor410 are fabricated from suitable electrical insulators 411 and 441,respectively.

Internally, capacitor 410 comprises a plurality of charge-storing plates415 and 416. Plates 415 are to store charge having a first polarity, andplates 416 are to store charge having a second polarity.

Terminal 421 is electrically coupled to plates 415. Terminals 413 and429 are also electrically coupled to plates 415 by means of conductorsor vias 420. Vias 420 pass through non-contact or keep-out areas, suchas keep-out areas 417, in plates 416.

Terminal 422 is electrically coupled to plates 416. Terminals 414 and428 are also electrically coupled to plates 416 by means of conductorsor vias 419. Vias 419 pass through non-contact or keep-out areas, suchas keep-out areas 418, in plates 415.

In this embodiment, electrical element 401 comprises a substrate 402 ofelectrically insulating material. Electrical element 401 furthercomprises a plurality of terminals, including terminals 405, 406, 409,and 412. Terminals 405, 406, 409, and 412 can be of any suitable type,including conductive bumps or conductive bars. The terminals ofelectrical element 401 can be electrically coupled to correspondingconductors or traces of electrical element 401. For example, terminal405 is coupled to trace 403; terminal 412 is coupled to trace 408;terminal 409 is coupled to trace 407; and terminal 406 is coupled totrace 404. Substrate 402 can comprise one or more layers of traces. Manyother configurations of terminals and traces are possible, dependingupon the particular application.

Electrical element 401 is an electrical component that can perform anytype of function. In one embodiment, electrical element 401 is aprocessor integrated circuit (IC), which can be of any type, such as butnot limited to a microprocessor, a microcontroller, a complexinstruction set computing (CISC) microprocessor, a reduced instructionset computing (RISC) microprocessor, a very long instruction word (VLIW)microprocessor, a graphics processor, a digital signal processor (DSP),or any other type of processor or processing circuit. Other types ofelectrical elements 401 include a custom circuit, anapplication-specific integrated circuit (ASIC), a communicationscircuit, and a wireless filter circuit.

In addition, electrical element 401 can be another capacitor havingseparate terminals on three or more sides. In such embodiment,electrical element 401 can be identical to or different from capacitor410.

Still referring to the embodiment of FIG. 13, substrate 430 can be aprinted circuit board (PCB) comprising one or more layers of traceswithin an insulating material 437. Substrate 430 comprises a pluralityof terminals, including terminals 424, 425, 435, and 436 on or in itsupper surface. Terminals 424, 425, 435, and 436 can be of any suitabletype, including conductive pads or bars. In the embodiment shown,terminals 424 and 425 are conductive pads, and terminals 435 and 436 areconductive bars (referred to in some embodiments as “Alternative BumpMetallurgy” (ABM)).

The terminals of substrate 430 can be electrically coupled tocorresponding conductors or traces of substrate 430. For example,conductive bars 435 and 436 are coupled to conductors 431 and 432,respectively, which in turn are coupled to terminals 433 and 434,respectively, on the lower surface of substrate 430. Terminals 424 and425 are coupled to traces 426 and 427, respectively.

As mentioned above, electronic assembly 400 can be implemented in manydifferent forms. In one embodiment, electronic assembly 400 comprisescapacitor 410 electrically coupled to electrical element 401. In thisembodiment, terminals (such as terminals 413 and 414) on the uppersurface of capacitor 410 are electrically coupled to correspondingterminals (such as terminals 412 and 409) on electrical element 401. Inaddition, separate terminals on opposite sides of capacitor 410 (such asterminals 421 and 422) are electrically coupled to correspondingterminals on electrical element 401. In this embodiment, the conductivebars 435 and 436 would be formed on and as part of electrical element401 rather than on and as part of substrate 430.

In another embodiment, electronic assembly 400 comprises capacitor 410electrically coupled to substrate 430. In this embodiment, terminals(such as terminals 428 and 429) on the lower surface of capacitor 410are electrically coupled to corresponding terminals (such as terminals424 and 425) on substrate 430. In addition, separate terminals onopposite sides of capacitor 410 (such as terminals 421 and 422) areelectrically coupled to corresponding terminals on substrate 430. Inthis embodiment, terminals 421 and 422 of capacitor 410 are electricallycoupled to conductive bars 435 and 436, respectively, of substrate 430.

In yet another embodiment, electronic assembly 400 comprises capacitor410 electrically coupled to both electrical element 401 and to substrate430. In such embodiment, the terminals (such as terminals 428 and 429)on the lower surface of capacitor 410 are electrically coupled tocorresponding terminals (such as terminals 424 and 425) on or in theupper surface of substrate 430. Terminals on opposite ends of capacitor410 (such as terminals 421 and 422) are electrically coupled toconductive bars 435 and 436, respectively, which can be formed on and aspart of either substrate 430 or electrical element 401. Terminals (suchas terminals 413 and 414) on the upper surface of capacitor 410 areelectrically coupled to corresponding terminals (such as terminals 412and 409) of electrical element 401. In addition, in an embodimentwherein conductive bars 435 and 436 are formed on and as part ofsubstrate 430, terminals 405 and 406 of electrical element 401 areelectrically coupled to conductive bars 435 and 436, respectively, ofsubstrate 430.

The terminals of the electrical element 401, of the capacitor 410, andof the substrate 430 can be formed of any suitable material, includingmetals or metal alloys known to those of ordinary skill in the art, suchas lead, solder, copper, silver, aluminum, gold, etc.

FIGS. 14A and 14B together illustrate a flow diagram of a method offabricating a multi-terminal capacitor having separate terminals onthree or more sides, in accordance with an embodiment of the inventivesubject matter. The method starts at 500.

In 501, a capacitor is constructed having two sets of charge-storingelements. Each set comprises at least one charge-storing element. Forexample, a first set of charge-storing elements has a firstcharge-storing element to store a charge having a first polarity, e.g. apositive polarity. A second set of charge-storing elements has a secondcharge-storing element to store a charge having a second polarity, e.g.a negative polarity. The sets of charge-storing elements are separatedby a dielectric material, such as any of those mentioned earlier.

In 503, P separate terminals are formed on at least three of theexternal sides of the capacitor. M of the P separate terminals arecoupled to the first charge-storing element(s). N of the P separateterminals are coupled to the second charge-storing elements(s). “M”,“N”, and “P” are positive integers, and P=M+N. For example, withreference to FIG. 11, there are 4 separate terminals on the uppersurface of capacitor 200, 4 separate terminals on the lower surface, andseparate terminals on each of the left, right, front, and back sides,giving a total of P=12 separate terminals. M=6 of the 12 terminals arecoupled to a first set of charge-storing elements (e.g. plates 221 and22), and N=6 of the 12 terminals are coupled to a second set ofcharge-storing elements (e.g. plates 223 and 224)

The capacitor can be made in different embodiments, having at least 3,4, 5, or 6 separate terminals formed on 3, 4, 5, or 6 different exteriorsides, respectively, of the capacitor. For example, FIG. 5 illustratesan embodiment having separate terminals on 3 sides. FIG. 8 illustratesan embodiment having separate terminals on 4 sides. And FIG. 11illustrates embodiments having separate terminals on either 5 or 6sides.

The capacitor can have more than one separate terminal on each of atleast 3 exterior sides. For example, one exterior side could have 2separate terminals; another side could have 3 separate terminals; athird exterior side could have 7 separate terminals; a fourth exteriorside could have just 1 separate terminal; and so forth.

The capacitor has a body, which may have any suitable geometrical shape.In one embodiment, e.g. as shown in FIG. 5, the capacitor body has thegeometrical shape of a rectangular solid. However, other geometricalsolids are possible, such as cylinders, truncated cones, trapezoidalsolids, free-form solids, and the like. The method ends at 505.

FIGS. 15A and 15B together illustrate a flow diagram of a method offabricating an electronic assembly comprising a substrate and amulti-terminal capacitor having separate terminals on three or moresides, in accordance with an embodiment of the inventive subject matter.The method starts at 600.

At 601, a capacitor having separate terminals on at least 3 sides ispositioned with respect to a substrate.

At 603, a separate terminal of a first side is electrically coupled to afirst terminal on the substrate. In another embodiment (e.g. that shownin FIG. 13), 2 separate terminals (428, 429) of a first side areelectrically coupled to first and second terminals (424, 425),respectively, on the substrate. In yet another embodiment, one separateterminal of a first side is electrically coupled to first and secondterminals, respectively, on the substrate. For example, one bar-shapedterminal of a first side of the capacitor can be electrically coupled toseveral pads on the substrate.

At 605, a separate terminal of a second side is electrically coupled toa first conductive bar on the substrate. For example, with reference toFIG. 13, terminal 421 is electrically coupled to conductive bar 435. Inanother embodiment, 2 separate terminals of a second side areelectrically coupled to a first conductive bar on the substrate. Forexample, 2 separate terminals of a second side of the capacitor can beelectrically coupled to a first conductive bar on the substrate.

At 607, a separate terminal of a third side is electrically coupled to asecond conductive bar on the substrate. For example, with reference toFIG. 13, terminal 422 is electrically coupled to conductive bar 436. Inanother embodiment, 2 separate terminals of a third side areelectrically coupled to a second conductive bar on the substrate. Forexample, 2 separate terminals of a third side of the capacitor can beelectrically coupled to a second conductive bar on the substrate. Themethod ends at 609.

FIGS. 16A, 16B, and 16C together illustrate a flow diagram of a methodof fabricating an electronic assembly comprising a substrate, anelectrical element, and a multi-terminal capacitor having separateterminals on three or more sides, in accordance with an embodiment ofthe inventive subject matter. The method starts at 700.

At 701, a capacitor having “P” separate terminals on at least 3 exteriorsides is positioned adjacent to a substrate having “M” terminals. Insome embodiments, the capacitor has separate terminals on 4, 5, or 6sides. The capacitor may have more than one separate terminal per side.The M terminals on the substrate may include at least one conductivebar.

At 703, an electrical element, such as electrical element 401 in FIG.13, is positioned adjacent to the capacitor. The electrical element has“N” terminals. The N terminals of the electrical element may include atleast one conductive bar.

At 705, the capacitor's P separate terminals are electrically coupled tothe M terminals on the substrate and to the N terminals of theelectrical element. This can be done in many different ways, dependingupon the arrangement of terminals on the capacitor, and upon thearrangement of terminals, including conductive bars, on the substrateand on the electrical element.

In one embodiment, one or more separate terminals of a first side of thecapacitor may be electrically coupled to corresponding terminals of thesubstrate. One or more separate terminals of a second side may beelectrically coupled to a first conductive bar on the substrate. One ormore separate terminals of a third side may be electrically coupled to asecond conductive bar on the substrate. One or more conductive terminalsof a fourth side may be electrically coupled to corresponding terminalsof the electrical element. One or more separate terminals of a fifthside may be electrically coupled to a first conductive bar on theelectrical element. One or more separate terminals of a sixth side maybe electrically coupled to a second conductive bar on the electricalelement. That is, both the substrate and the electrical element couldhave one or more conductive bars in or on their respective surfaces, towhich separate terminals of the same or different sides of the capacitorcould be electrically coupled.

Many combinations of capacitor terminals, of electrical elementterminals, and of substrate terminals are possible besides those shownand described. In general, the separate terminals can be coupled tocorresponding terminals and/or conductive bars on the substrate and/oron the electrical element in any desired combination. The method ends at707

The operations described above with respect to the methods illustratedin FIGS. 14A–B, 15A–B, and 16A–C can be performed in a different orderfrom those described herein.

The above-described and illustrated details relating to the number,arrangement, dimensions, and types of terminals, electrical elements,substrates, and other constituent parts are merely exemplary of theembodiments illustrated, and they are not meant to be limiting. Further,the assembly operations and sequencing can be varied by one of ordinaryskill in the art to optimize the fabrication and performance of thecapacitor and/or electronic assembly.

FIGS. 1–13 are merely representational and are not drawn to scale.Certain proportions thereof may be exaggerated, while others may beminimized. The drawings are intended to illustrate variousimplementations of the inventive subject matter that can be understoodand appropriately carried out by those of ordinary skill in the art.

The inventive subject matter present invention provides for a multilayercapacitor that has separate terminals on at least three sides, and on asmany as six sides. The capacitors can be fabricated in a large number ofdifferent configurations, types, and sizes, depending upon the desiredend use application.

In embodiments, described in the Related Applicationsm, the capacitorsprovide high-speed, low inductance capacitive decoupling in anintegrated circuit (IC) package, in which the capacitors are positionedwithin the mounting region between a die and an IC package substrate.

In another embodiment, a capacitor, having separate terminals on atleast three different sides, is mounted on a substrate, and anelectrical element can optionally be mounted on the capacitor.Alternatively, the capacitor could be mounted on the electrical elementalone.

In yet another embodiment, a capacitor, having separate terminals on upto six different sides, is mounted between conductive bars on asubstrate surface, and the capacitor may be electrically coupled to theconductive bars, to one or more terminals on the substrate, to one ormore terminals of an electrical element, and to one or more terminals ofadjacent capacitors. Alternatively, the capacitor could be mountedbetween conductive bars on the surface of an electrical element. Or thecapacitor could be mounted between conductive bars that are on both thesubstrate and on the electrical element.

The separate terminals that are disposed on different sides of thecapacitor can be readily coupled to a variety of different adjacentconductors, such as die terminals (including bumpless terminals), ICpackage terminals (including pads and/or bars), and the terminals ofadjacent discrete components (including additional capacitors). Inaddition to the types of terminals described above, any other suitableterminals could be used. The terminals can have any desired geometry,location on the component, and composition.

Methods of fabrication, as well as application of the capacitors to anelectronic assembly, are also described.

The inventive subject matter present invention allows electronicassemblies with high performance ICs to be operated at increased clockfrequencies and with higher reliability. An electronic assembly and/orelectronic system that incorporates one or more capacitors of theinventive subject matter can handle the relatively high power densitiesand clock frequencies associated with high performance ICs, and suchassemblies and/or systems are therefore more commercially attractive.

As shown herein, the inventive subject matter can be implemented in anumber of different embodiments, including various types of capacitors,an electronic assembly, and various methods of fabricating a capacitorand an electronic assembly. Other embodiments will be readily apparentto those of ordinary skill in the art. The elements, materials,geometries, dimensions, and sequence of operations can all be varied tosuit particular manufacturing and packaging requirements.

While certain structures or operations have been described hereinrelative to the reader's perspective, such as “top” or “bottom”, “upper”or “lower”, “left” or “right”, “front” or “rear”, and so forth, it willbe understood that these descriptors are relative, and that they wouldbe reversed if the particular structure being described, e.g. acapacitor, IC, substrate, or package, were inverted, rotated, or viewedin mirror-image. Therefore, these terms are not intended to be limiting.

The inventive subject matter is not to be construed as limited to use inIC packages, and it can be used with any other type of electronicpackage where the herein-described features of the inventive subjectmatter provide an advantage.

Although specific embodiments have been illustrated and describedherein, it will be appreciated by those of ordinary skill in the artthat any arrangement that is calculated to achieve the same purpose maybe substituted for the specific embodiment shown. This application isintended to cover any adaptations or variations of the inventive subjectmatter. Therefore, it is manifestly intended that this inventive subjectmatter be limited only by the claims and the equivalents thereof.

1. A capacitor comprising: a body having an interior and a plurality ofexterior sides; a first element to hold an electrical charge of a firstpolarity; a second element to hold an electrical charge of a secondpolarity; first and second terminals coupled to the first and secondelements, respectively, and disposed on first and second ones of theplurality of exterior sides; at least one conductor within the interior;at least one additional conductor within the interior; a third terminalcoupled to the first element and disposed on a third one of theplurality of exterior sides, wherein the third terminal is electricallycoupled to the first terminal only via the first element and the atleast one conductor; a fourth terminal coupled to the second element anddisposed on a fourth one of the plurality of exterior sides, wherein thefourth terminal is electrically coupled to the second terminal only viathe second element; and a fifth terminal coupled to the second elementand disposed on a fifth one of the plurality of exterior sides, whereinthe fifth terminal is electrically coupled to the second terminal onlyvia the second element and the at least one additional conductor.
 2. Thecapacitor recited in claim 1, wherein the third and fifth exterior sidesare on opposite sides of the body.
 3. The capacitor recited in claim 1,wherein the first and second elements are within the interior.
 4. Thecapacitor recited in claim 1, wherein the first element is separatedfrom the second element by a dielectric material.
 5. The capacitorrecited in claim 1, wherein the body has a geometrical shape of arectangular solid.
 6. The capacitor recited in claim 1 and furthercomprising: a sixth terminal coupled to the first element and disposedon a sixth one of the plurality of exterior sides, wherein the sixthterminal is electrically coupled to the first terminal only via thefirst element.
 7. The capacitor recited in claim 6, wherein the fourthand sixth exterior sides are on opposite sides of the body.